Blaenplwyf transmitting station

Blaenplwyf
Mast height 152 metres (499 ft)
Coordinates 52°22′N 4°06′W / 52.36°N 4.1°W / 52.36; -4.1Coordinates: 52°22′N 4°06′W / 52.36°N 4.1°W / 52.36; -4.1
BBC region BBC Wales
ITV region ITV Wales

The Blaenplwyf transmitting station (sometimes written "Blaen Plwyf" or "Blaen-Plwyf") is a broadcasting and telecommunications facility located near the village of Blaenplwyf about 10 kilometres (6 mi) to the south west of the town of Aberystwyth, in Ceredigion, Wales (grid reference SN569756). It was originally built by the BBC, entering service in October 1956 acting as a main transmitter for BBC Band II VHF FM radio.

It had been planned that the BBC's 405-line VHF television service would commence on the same date, but delays at Rowridge[1] caused the official switch-on to happen six months later on 29 April 1957.[2][3] Blaenplwyf was considered a main transmitter for VHF television (despite radiating only 3 kW ERP) as it was fed from a microwave link from Mynydd Pencarreg just south of Lampeter.

The facility is now owned and operated by Arqiva.

The site has a 152 metres (499 ft) guyed steel lattice mast standing on land that is itself 175 metres (574 ft) above sea level. The television and radio broadcasts were originally designed to cover the majority of the Cardigan Bay coastline, the antennas being designed for maximum ERP to the north and to the south-west.

Blaenplwyf became a main transmitter for UHF analogue colour television from 1970 onwards, and was transmitting all three original UHF channels in colour from mid 1973.[4]

It currently carries all six UK digital television multiplexes.

Services listed by frequency

Analogue television

29 April 1957 - Summer 1970

Newspaper articles[5][6] claimed that at launch, the television service would be 1 kW. The technical report from the BBC[7] disagrees, pointing out that the mean ERP was 0.8 kW at launch, and was uprated to twice that value on 8 August 1958.

This report also points out that the signal had its maximum ERP lobe to the north, and that this had been 1.6 kW at launch and 3.2 kW after the power increase. Also, that the coastal towns to the south-west had been treated to the weakest ERP (0.5 kW at launch, 1.0 kW later). Amongst the effects of this were to leave the town of Cardigan with no signal.

Frequency VHF kW Service
56.75 MHz 3 1.6 (3.2 from August 1958) BBC TV

Summer 1970 - 7 May 1973

BBC2 625-line UHF colour television services came to Blaenplwyf in 1970 (early for Wales). VHF television continued as before. The service area for UHF however was designed to cover more of inland mid Wales than the VHF service had been.

Frequency VHF UHF kW Service
56.75 MHz 3 — 3 BBC1 Wales
519.25 MHz — 27 100 BBC2 Wales

7 May 1973 - 1 November 1982

A full (3-channel) 625-line UHF colour television service was in operation from Blaenplwyf as of 1973 with the introduction of the HTV Wales service.

Frequency VHF UHF kW Service
56.75 MHz 3 — 3 BBC1 Wales
495.25 MHz — 24 100 HTV Wales
519.25 MHz — 27 100 BBC2 Wales
551.25 MHz — 31 100 BBC1 Wales

1 November 1982 - January 1985

The launch of Channel 4 (S4C in Wales) took the UHF capabilities of the site to its design maximum. Being in Wales, this transmitter radiated the S4C variant.

Frequency VHF UHF kW Service
56.75 MHz 3 — 3 BBC1 Wales
471.25 MHz — 21 100 S4C
495.25 MHz — 24 100 HTV Wales
519.25 MHz — 27 100 BBC2 Wales
551.25 MHz — 31 100 BBC1 Wales

January 1985 - 30 March 1997

28 years of VHF television from this site came to an end in 1985 as the entire 405-line VHF TV system was switched off across the UK. Blaenplwyf continued with its four UHF channels.

Frequency UHF kW Service
471.25 MHz 21 100 S4C
495.25 MHz 24 100 HTV Wales
519.25 MHz 27 100 BBC2 Wales
551.25 MHz 31 100 BBC1 Wales

30 March 1997 - 15 November 1998

Despite the fact that the UK's UHF TV system had only been engineered for four TV channels, a fifth was added in 1997. In common with the situation across much of the UK, Blaenplwyf was forced to transmit this extra service well out-of-group and at low power compared with the main four.

Frequency UHF kW Service
471.25 MHz 21 100 S4C
495.25 MHz 24 100 HTV Wales
519.25 MHz 27 100 BBC Two Wales
551.25 MHz 31 100 BBC One Wales
751.25 MHz 56 4 Channel 5

Analogue and digital television

15 November 1998 - 10 February 2010

The UK's initial experimental digital television service was rolled out, using low power for the transmissions and interleaved with the analogue transmissions in an attempt to make the whole set receivable with the original aerial group.

Frequency UHF kW Service System
471.25 MHz 21 100 S4C PAL System I
482.166 MHz 22+ 2 Digital 3&4 (Mux 2) DVB-T
495.25 MHz 24 100 ITV1 Wales (HTV Wales until 2002) PAL System I
506.166 MHz 25+ 2 SDN (Mux A) DVB-T
519.25 MHz 27 100 BBC Two Wales PAL System I
530.166 MHz 28+ 2 BBC (Mux 1) DVB-T
538.166 MHz 29+ 1 Arqiva (Mux C) DVB-T
551.25 MHz 31 100 BBC One Wales PAL System I
562.166 MHz 32+ 2 BBC (Mux B) DVB-T
570.166 MHz 33+ 1 Arqiva (Mux D) DVB-T
751.25 MHz 56 4 Channel 5 PAL System I

10 February 2010 - 10 March 2010

Digital Switchover started at Blaenplwyf. The BBC Two analogue service on channel 27 was closed down after 40 years of service. Multiplex 1 from channel 28+ was also closed and the new BBC multiplex A commenced on channel 27 at its intended full power and using 64-QAM mode and 8k carriers from the start.

Frequency UHF kW Service System
471.25 MHz 21 100 S4C PAL System I
482.166 MHz 22+ 2 Digital 3&4 (Mux 2) DVB-T
495.25 MHz 24 100 ITV1 Wales PAL System I
506.166 MHz 25+ 2 SDN (Mux A) DVB-T
522.000 MHz 27 40 BBC A DVB-T
538.166 MHz 29+ 1 Arqiva (Mux C) DVB-T
551.25 MHz 31 100 BBC One Wales PAL System I
562.166 MHz 32+ 2 BBC (Mux B) DVB-T
570.166 MHz 33+ 1 Arqiva (Mux D) DVB-T
751.25 MHz 56 4 Channel 5 PAL System I

Digital television

10 March 2010 - present

Digital switchover was completed, seeing the shutdown of all the remaining analogue TV services from this site. The new digital multiplexes took over the frequencies of the analogue services plus a few new ones.

Frequency UHF kW Operator
474.166 MHz 21+ 40 BBC B
482.166 MHz 22+ 10 Arqiva A
498.000 MHz 24 40 Digital 3&4
506.000 MHz 25 10 SDN
522.000 MHz 27 40 BBC A
530.000 MHz 28 10 Arqiva B

Analogue radio (FM VHF)

14 October 1956 - August 1968

Blaenplwyf started transmitting VHF FM radio only a year and a half after the then-novel service was initiated in the UK.[8] At launch, the service was from temporary transmitters using a temporary mast, but from 29 April 1957 the main transmitters came into service with antennas on the main mast. These transmitters were 60 kW each.[9]

In 1960 the BBC published a technical report[10] showing the measured service area of the FM radio services (plus those of Moel y Parc and Llanddona).

Frequency kW Service
88.7 MHz 60 BBC Light Programme
90.9 MHz 60 Third Programme
93.1 MHz 60 Welsh Home Service

August 1968 - May 1978

The names of the radio services changed in the late 1960s, but the number of services available remained the same, as did the ERPs.[11]

Frequency kW Service
88.7 MHz 60 BBC Radio 2
90.9 MHz 60 BBC Radio 3
93.1 MHz 60 BBC Radio 4 Wales

May 1978 - Late 1980s

Radio 1 started to share the Radio 2 VHF allocations during the late 1970s. Radio Cymru had taken over the 93.1 MHz slot. The ERPs of all three services were still unchanged.[12]

Frequency kW Service
88.7 MHz 60 BBC Radio 1/BBC Radio 2
90.9 MHz 60 BBC Radio 3
93.1 MHz 60 Radio Cymru

Late 1980s

The ERP had been uprated in the years since 1978. More services had been added.[13]

Frequency kW Service
88.7 MHz 250 BBC Radio 2
90.9 MHz 250 BBC Radio 3
93.1 MHz 250 BBC Radio Cymru
98.3 MHz 250 BBC Radio 1
104.0 MHz 250 BBC Radio 4

January 2012

More services have been added since the late 1980s.[14][15][16] The latter of these references notes that the Classic FM and Radio Ceredigion services are radiated from a point only 80 m (262 ft) up the mast, and together with the low ERPs of those two services, the coverage should be expected to be limited.

From 4 January 2011, Real Radio was added to the set.[17] Real Radio's OFCOM application claims they intended to radiate 10 kW and 2.5 kW beams.[18]

Frequency kW Service
88.7 MHz 250 BBC Radio 2
90.9 MHz 250 BBC Radio 3
93.1 MHz 250 BBC Radio Cymru
95.3 MHz 120 BBC Radio Wales
98.3 MHz 250 BBC Radio 1
101.1 MHz 10 Classic FM
103.3 MHz 6 Radio Ceredigion
104.0 MHz 250 BBC Radio 4
107.7 MHz 10 Real Radio North Wales

See also

References

  1. ↑ "Rowridge History". TheBigTower. Retrieved 28 May 2013.
  2. ↑ http://www.ceredigion.gov.uk/utilities/action/act_download.cfm?mediaid=22524&langtoken=eng
  3. ↑ http://www.ceredigion.gov.uk/utilities/action/act_download.cfm?mediaid=22525&langtoken=eng
  4. ↑ "Welcome to the Gallery Upgrader". Txlib.mb21.co.uk. Retrieved 28 May 2013.
  5. ↑ http://www.ceredigion.gov.uk/utilities/action/act_download.cfm?mediaid=22526&langtoken=eng
  6. ↑ http://www.ceredigion.gov.uk/utilities/action/act_download.cfm?mediaid=22527&langtoken=eng
  7. ↑ http://downloads.bbc.co.uk/rd/pubs/reports/1958-30.pdf
  8. ↑ http://www.nonstopsystems.com/radio/article-hell-bbc-broadcst.pdf[]
  9. ↑ http://www.ceredigion.gov.uk/utilities/action/act_download.cfm?mediaid=22523&langtoken=eng
  10. ↑ http://downloads.bbc.co.uk/rd/pubs/reports/1960-24.pdf
  11. ↑ "Welcome to the Gallery Upgrader". Txlib.mb21.co.uk. Retrieved 28 May 2013.
  12. ↑ "Welcome to the Gallery Upgrader". Txlib.mb21.co.uk. Retrieved 28 May 2013.
  13. ↑ "Welcome to the Gallery Upgrader". Txlib.mb21.co.uk. Retrieved 28 May 2013.
  14. ↑ "Help receiving TV and radio - Transmitters". BBC. 1 January 1970. Retrieved 28 May 2013.
  15. ↑ "Television and Radio Reception in Aberystwyth". Aberystwyth.org.uk. Retrieved 28 May 2013.
  16. ↑ "Blaenplwyf FM transmitter info". Fmscan.org. Retrieved 28 May 2013.
  17. ↑ "Digital Radio in Wales, UK". Real Radio Wales. 24 May 2013. Retrieved 28 May 2013.
  18. ↑ "Real Radio North wales - Page 2 - Radio - Digital Spy Forums". Forums.digitalspy.co.uk. Retrieved 28 May 2013.

External links

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